Replacing wood with biochar in hugelkultur?

Has anyone here tried making a bed like a hugel bed, but replacing the wood with biochar? Or know someone who has tried?

For the sake of retaining water and nutrients and making a home for soil life, it seems like it should work on paper. And it degrades very, very slowly.
I'd be interested to hear your thoughts.

Jay C. White Cloud

Posts: 2413

46

posted 2 years ago

Hi Mathew, et al,

We call this "mound gardening" in our traditions...not hugelkultur...yet the two forms are virtually identical. Several big differences is that we stratify dead animals...bones and all...in layers of charred as well as whole wood pieces. So yes it has been done...and to good effect. Hope you try it and let us know your results.

Regards,

j

Roger Taylor

Posts: 103

Location: New Zealand

3

posted 2 years ago

1

Matthew McCoul wrote:Has anyone here tried making a bed like a hugel bed, but replacing the wood with biochar? Or know someone who has tried?

For the sake of retaining water and nutrients and making a home for soil life, it seems like it should work on paper. And it degrades very, very slowly.
I'd be interested to hear your thoughts.

Sort of.

I have three hugel beds. I didn't quite use biochar, but what I did use was burnt logs. Farmers like my neighbour pile all their cleared wood and trunks in a pile, and set it on fire. I went through what was left and took as many as I could transport. I planned to use them to make the hugelbeds, and hopefully gain some of the benefits of biochar. In practice, I wouldn't be surprised if it just meant that bits of wood which wouldn't decompose were going to be in the ground under my vegetables. Not sure it matters for me, as the primary benefit of a hugel bed for me is that it raises the plants out of the ground where they would otherwise get drowned when it rains.

Bed one has spinach, leeks, cabbage, broccoli and garlic. Only the leeks and garlic look like they're doing fine. The others are lacklustre.

Bed two and three has broken up pieces of rhubarb crown. These last year drowned twice. This is where they sit in water, then the leaves die off, and the stalks wilt along with them. Being on a slope raised in a hugel bed, I have great expectations for these.

Honestly, I think it's a no brainer. If you have good stuff to put in your garden, then put it in there. When I was making mine, I threw in compost, used potting mix, cow dung, sheep shit, chickenpoop and junk mail for good measure. The worms love it. Nearly everywhere I poked a hole to put a garlic clove in, the worms got in the road of the clove insertion. If everyone who was making a hugel bed had a surfeit of biochar, I imagine we'd all be using it appropriately.

I've done similar to what Roger is talking about with good success. I've sourced the majority of my wood from burnt slash piles on our property from a previous logging operation. It seems like you would be looking at a massive amount of biochar if one were to use it exclusively to make any kind of a sizable hugel bed. This just seems like an unreasonable amount of work when you start talking about six or twelve foot tall hugel beds, but it would likely be a one time shot for the next several hundred years so....

on a side note: I also use the soil from the same slash piles to make my hugel mounds, and this stuff contains a good amount of char and has proven to be quite fertile.

I have to agree with the above two guys that in the real world you would be making your hugelK mound from a mix of char and wood as in charred wood. A mix of wood and char just "feels" like it would work better. Making large amounts of bio-char for large hugelK- is too time consuming.......

You could start a nice size bonfire then at the right time hose it down to extinguish it. Bury what is left in a hugelK